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Pet Fiddler Crab Care

David Cory is an animal enthusiast. He currently has a 29 gallon tank filled with both male and female fiddler crabs.

Our planet contains a large number of fiddler crab species, all belonging to the genus Uca. They typically are found in brackish environments (not salt water but not completely freshwater either) and are carnivorous. They spend their lives in both water and on land.

Fiddler crabs are a more unusual pet choice, but the level of care and amount of time involved is really not all that great. Fiddler crabs are best suited for life in a tank with other fiddlers. Their antics are more than enough to provide you with the certainty that you made a good decision in acquiring these small crustaceans. In addition, given their relatively small size they are perfect for most any home.

A male fiddler crab

A male fiddler crab

Fiddler Crab Overview

Pet fiddler crab care can be divided into the following categories:

1) Diet

2) Habitat

3) Water Care

4) Continued Maintenance

5) Molting

6) Fiddler Crab Community

"Until one has loved an animal a part of one's soul remains unawakened."

— Anatole France

1) Diet

Fiddler crabs need carnivorous foods such as shrimp or bloodworms. Perhaps the easiest is freeze dried, but far better is frozen. Frozen food gives fiddler crabs a more palatable food to which they are better attracted. Frozen food can be found in both cubed or whole sheets. The cost for these types of food is minimal so be sure to purchase a variety. Doing so will give your fiddler crabs a more diverse diet and aid in their overall health. The crabs can be either once or twice a day so as long as they are not overfed.

2) Habitat

Another important part of fiddler crab husbandry is shelter. Ideally a large fish tank would be used as it would best be able to house many crabs comfortably. Anything 10 gallons or larger would be appropriate.

LED lighting from above is recommended as it is energy efficient and does not overheat. And unlike florescent type lighting, LED lights produce no noise or buzzing sounds. They are the best option currently available. A good LED light strip to choose is shown below.

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With a 12 hour on/off cycle your fiddler crabs will do well. Investing in a basic timer allows for consistent on/off times.

Gravel and a few tank decorations should certainly be added with water coming about a third of the way up the tank. This will allow the fiddler crabs access to both land and water which is vital to their health.

Fiddler Crab Habitat Checklist

A large tank

Water dechlorinator

Heater for the water

Gravel (about 1-2 inches deep)

A bucket for water changes

Aquarium Hood (lid)

Decorations such a drift wood or large rocks

Filter (in-tank filters work the best)

LED light fixture

An example of an ideal fiddler crab tank setup.

An example of an ideal fiddler crab tank setup.

3) Water Care

Similar to the care an aquarium would need, the water in a fiddler crab tank needs weekly maintenance. Once a week check for uneaten food, excessive algae growth, and the general cleanliness of the tank. Take out 10 to 20 percent of the water and replace it with clean, properly conditioned tap water using a pet store dechlorinator. Scrub the wall with an algae scrubber if needed.

4) Continued Maintenance

As an ongoing part of owning fiddler crabs, you will need to maintain the tank and all equipment used. Every month inspect the filter and air pump (if using one) for clogs or buildup of debris. If you didn't do any water changes during the preceding month then go ahead and do a 25 percent water change. Also, take time to look at the crabs for signs of illness. The sooner you spot any problems, the sooner you can get your crabs treated.

While fiddler crabs aren't the most demanding of pets it is certainly a good idea to keep up with maintenance. Many problems can be prevented by doing the tasks outlined above.

5) Molting

Fiddler crabs have an exoskeleton and will from time to time molt it in order to grow. When fiddler crabs are young they tend to molt frequently. Later in the fiddler crab's life the rate of molting will slow down.

After a fiddler crab has emerged from the old exoskeleton it will then eat it for the nutrients. This may seem odd, but in fact it is an example of nature letting nothing go to waste.

A fiddler crab after it molted.  The exoskeleton can be seen next to the crab.

A fiddler crab after it molted. The exoskeleton can be seen next to the crab.

6) Crab Community

Fiddler crabs do well in a community setup. Always make sure not to overcrowd your tank and be sure to keep a mixture of both males and females. In a tank like this it will be possible for the male and female crabs to mate. It is, however, unlikely that the eggs will mature into adult crabs. This typically requires an environment that only nature itself can provide.

Fiddler crabs are mildly aggressive, but one way to reduce this tendency is to keep them well fed and again making sure the tank is not overcrowded. Keeping up with filter and water maintenance will allow for a slightly higher number of crabs to be kept together.

A tank with several different types of decoration is suggested. Examples of proper décor would include larger rocks, resin based pet store items like driftwood, and small hiding areas. Always be sure to keep the lid on your tank tightly closed as fiddler crabs are excellent at escaping if given an opportunity.

Enjoy Your New Pets

Remember to just have fun. Having sufficient knowledge in pet fiddler crab care will provide you with healthy, active pets. And your decision to own pet fiddler crabs will not disappoint. It might even inspire other to care for these unique, interesting pets. Enjoy!

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2018 David Cory

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